IAMP News Bulletin October 2015
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Supergravity and Its Legacy Prelude and the Play
Supergravity and its Legacy Prelude and the Play Sergio FERRARA (CERN – LNF INFN) Celebrating Supegravity at 40 CERN, June 24 2016 S. Ferrara - CERN, 2016 1 Supergravity as carved on the Iconic Wall at the «Simons Center for Geometry and Physics», Stony Brook S. Ferrara - CERN, 2016 2 Prelude S. Ferrara - CERN, 2016 3 In the early 1970s I was a staff member at the Frascati National Laboratories of CNEN (then the National Nuclear Energy Agency), and with my colleagues Aurelio Grillo and Giorgio Parisi we were investigating, under the leadership of Raoul Gatto (later Professor at the University of Geneva) the consequences of the application of “Conformal Invariance” to Quantum Field Theory (QFT), stimulated by the ongoing Experiments at SLAC where an unexpected Bjorken Scaling was observed in inclusive electron- proton Cross sections, which was suggesting a larger space-time symmetry in processes dominated by short distance physics. In parallel with Alexander Polyakov, at the time in the Soviet Union, we formulated in those days Conformal invariant Operator Product Expansions (OPE) and proposed the “Conformal Bootstrap” as a non-perturbative approach to QFT. S. Ferrara - CERN, 2016 4 Conformal Invariance, OPEs and Conformal Bootstrap has become again a fashionable subject in recent times, because of the introduction of efficient new methods to solve the “Bootstrap Equations” (Riccardo Rattazzi, Slava Rychkov, Erik Tonni, Alessandro Vichi), and mostly because of their role in the AdS/CFT correspondence. The latter, pioneered by Juan Maldacena, Edward Witten, Steve Gubser, Igor Klebanov and Polyakov, can be regarded, to some extent, as one of the great legacies of higher dimensional Supergravity. -
PHYSICS BEYOND the STANDARD MODEL Jean Iliopoulos
PHYSICS BEYOND THE STANDARD MODEL Jean Iliopoulos To cite this version: Jean Iliopoulos. PHYSICS BEYOND THE STANDARD MODEL. 2008. hal-00308451v1 HAL Id: hal-00308451 https://hal.archives-ouvertes.fr/hal-00308451v1 Preprint submitted on 30 Jul 2008 (v1), last revised 13 Aug 2008 (v2) HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. LPTENS-08/45 PHYSICS BEYOND THE STANDARD MODEL JOHN ILIOPOULOS Laboratoire de Physique Th´eorique de L’Ecole Normale Sup´erieure 75231 Paris Cedex 05, France We review our expectations in the last year before the LHC commissioning. Lectures presented at the 2007 European School of High Energy Physics Trest, August 2007 Contents 1 The standard model 4 2 Waiting for the L.H.C. 6 2.1 Animpressiveglobalfit . .. .. .. .. .. 6 2.2 BoundsontheHiggsmass. 7 2.3 NewPhysics............................ 13 3 Grand Unification 17 3.1 The simplest G.U.T.: SU(5)................... 18 3.2 DynamicsofG.U.T.s. 23 3.2.1 Tree-level SU(5)predictions. 23 3.2.2 Higher order effects . 25 3.3 OtherGrandUnifiedTheories. 28 3.3.1 A rank 5 G.U.T.: SO(10) ................ 29 3.3.2 Othermodels ...................... -
Institut Des Hautes Ét Udes Scientifiques
InstItut des Hautes É t u d e s scIentIfIques A foundation in the public interest since 1981 2 | IHES IHES | 3 Contents A VISIONARY PROJECT, FOR EXCELLENCE IN SCIENCE P. 5 Editorial P. 6 Founder P. 7 Permanent professors A MODERN-DAY THELEMA FOR A GLOBAL SCIENTIFIC COMMUNITY P. 8 Research P. 9 Visitors P. 10 Events P. 11 International INDEPENDENCE AND FREEDOM, THE INSTITUTE’S TWO OPERATIONAL PILLARS P. 12 Finance P. 13 Governance P. 14 Members P. 15 Tax benefits The Marilyn and James Simons Conference Center The aim of the Foundation known as ‘Institut des Hautes Études Scientifiques’ is to enable and encourage theoretical scientific research (…). [Its] activity consists mainly in providing the Institute’s professors and researchers, both permanent and invited, with the resources required to undertake disinterested IHES February 2016 Content: IHES Communication Department – Translation: Hélène Wilkinson – Design: blossom-creation.com research. Photo Credits: Valérie Touchant-Landais / IHES, Marie-Claude Vergne / IHES – Cover: unigma All rights reserved Extract from the statutes of the Institut des Hautes Études Scientifiques, 1958. 4 | IHES IHES | 5 A visionary project, for excellence in science Editorial Emmanuel Ullmo, Mathematician, IHES Director A single scientific program: curiosity. A single selection criterion: excellence. The Institut des Hautes Études Scientifiques is an international mathematics and theoretical physics research center. Free of teaching duties and administrative tasks, its professors and visitors undertake research in complete independence and total freedom, at the highest international level. Ever since it was created, IHES has cultivated interdisciplinarity. The constant dialogue between mathematicians and theoretical physicists has led to particularly rich interactions. -
BEYOND the STANDARD MODEL Jean Iliopoulos Laboratoire De Physique Theorique´ De L’Ecole Normale Superieure,´ 75231 Paris Cedex 05, France
BEYOND THE STANDARD MODEL Jean Iliopoulos Laboratoire de Physique Theorique´ de L’Ecole Normale Superieure,´ 75231 Paris Cedex 05, France 1. THE STANDARD MODEL One of the most remarkable achievements of modern theoretical physics has been the construction of the Standard Model for weak, electromagnetic and strong interactions. It is a gauge theory based on the group U(1) SU(2) SU(3) which is spontaneously broken to U(1) SU(3). This relatively simple model epitomizes⊗ our⊗present knowledge of elementary particle interactions.⊗ It is analyzed in detail in the lectures of Prof. Quigg. Here I present only a short summary. The model contains three types of fields: [i] The gauge fields. There are twelve spin-one boson fields which can be classified into the (1; 8) ⊕ (3; 1) (1; 1) representation of SU(2) SU(3). The first eight are the gluons which mediate ⊕ ⊗ strong interactions between quarks and the last four are (W +; W −; Z0 and γ), the vector bosons of the electroweak theory. [ii] Matter fields. The basic unit is the “family” consisting exclusively of spinor fields. Until last year we believed that the neutrinos were massless and this allowed us to use only fifteen two-component complex fields, which, under SU(2) SU(3), form the representation (2; 1) (1; 1) (2; 3) ⊗ ⊕ ⊕ ⊕ (1; 3) (1; 3). We can⊕ still fit most experiments with only these fields, but there may be need, suggested by only one experiment, to introduce new degrees of freedom, possibly a right-handed neutrino. The prototype is the electron family: νe ui − ; νeR (??); eR; ; uiR ; diR e di !L !L 9 i = 1; 2; 3 : (1) > => (2; 1) (1; 1) (1; 1) (2; 3) (1; 3) (1; 3) > For the muon family νe νµ; e µ; ui ci and di si and, similarly;> , for the tau family, ! ! ! ! νe ντ ; e τ; ui ti and di bi. -
A Scale-Covariant Quantum Space-Time
A scale-covariant quantum space-time Claudio Perini∗ Institute for Gravitation and the Cosmos, Physics Department, Penn State, University Park, PA 16802-6300, USA Gabriele Nunzio Tornetta† School of Mathematics and Statistics, University of Glasgow, 15 University Gardens, G12 8QW, Scotland A noncommutative space-time admitting dilation symmetry was briefly mentioned in the seminal work [1] of Doplicher, Fredenhagen and Roberts. In this paper we explicitly construct the model in details and carry out an in-depth analysis. The C∗-algebra that describes this quantum space-time is determined, and it is shown that it admits an action by - automorphisms of the dilation group, along with the expected Poincar´ecovariance. In order∗ to study the main physical properties of this scale-covariant model, a free scalar neutral field is introduced as a investigation tool. Our key results are then the loss of locality and the irreducibility, or triviality, of special field algebras associated with regions of the ordinary Minkowski space-time. It turns out, in the conclusions, that this analysis allows also to argue on viable ways of constructing a full conformally covariant model for quantum space-time. I. INTRODUCTION In this paper we study a non-commutative space-time of DFR-type, that can be obtained as the limiting scale-free case of the original DFR model [1]. The main mathematical interest to study this model is that it is Poincar´e and dilation covariant, thus it possesses almost all the symmetries given by the conformal group. The issue of implementing the remaining symmetry, which is the relativistic ray inversion, is discussed in the concluding section. -
Radiotélescopes Seek Cosmic Rays
INTERNATIONAL JOURNAL OF HIGH-ENERGY PHYSICS CERN COURIER Radiotélescopes seek cosmic rays COMPUTING MEDICAL IMAGING NUCLEAR MASSES Information technology and Spin-off from particle physics Precision measurements from physics advance together pl6 wins awards p23 accelerator experiments p26 Multichannel GS/s data acquisition systems used For more information, to be expensive. They also would fill up entire visit our Web site at www.acqiris.com instrument racks with power-hungry electronics. But no more. We have shrunk the size, lowered 1)Rackmount kit available the cost, reduced the power consumption and incorporated exceptional features such as clock synchronization and complete trigger distribution.1) A single crate (no bigger than a desktop PC) can house up to 24 channels at 500MS/S or 1 GS/s when deploying an embedded processor, or up to 28 channels (14 at 2GS/s) using a PCI interface. CONTENTS Covering current developments in high- energy physics and related fields worldwide CERN Courier is distributed to Member State governments, institutes and laboratories affiliated with CERN, and to their personnel. It is published monthly except January and August, in English and French editions. The views expressed are not CERN necessarily those of the CERN management. Editor: Gordon Fraser CERN, 1211 Geneva 23, Switzerland E-mail [email protected] Fax +41 (22) 782 1906 Web http://www.cerncourier.com News editor: James Gillies COURIER VOLUME 41 NUMBER 3 APRIL 2001 Advisory Board: R Landua (Chairman), F Close, E Lillest0l, H Hoffmann, C Johnson, -
Reflections on the Renormalization Procedure for Gauge Theories
Reflections on the renormalization procedure for gauge theories Gerard ’t Hooft Institute for Theoretical Physics EMMEΦ Centre for Extreme Matter and Emergent Phenomena Science Faculty Utrecht University POBox 80.195 3808TD, Utrecht The Netherlands Internet: http://www.staff.science.uu.nl/˜hooft101/ In memory of Raymond Stora 1930 – 2015 Abstract Various pieces of insight were needed to formulate the rules for working with gauge theories of the electro-magnetic, weak and strong forces. First, it was needed to understand how to formulate the Feynman rules. We had to learn that there are many different ways to derive them, and it was needed to know arXiv:1604.06257v1 [hep-th] 21 Apr 2016 how different formulations of the gauge constraint lead to the same final re- sults: the calculated values of the scattering amplitudes. The rules for dealing with the infinities that had to be subtracted were a big challenge, culminating in the discovery of the Becchi-Rouet-Stora-Tyutin symmetry. Fond recollec- tions of the numerous discussions the author had with Raymond Stora on this topic are memorised here. We end with some reflections on the mathematical status of quantum field theories, and a letter sent by Stora to the author. Version: March 2016 Last typeset: April 22, 2016 1 1 Introduction Around the year 1970, rapid changes took place in our views of elementary particle physics, and in particular the role of local gauge theories and spontaneous symmetry breaking in these theories. For a long time, only few researchers had been convinced that quantum field theory was the way to go. -
Dark Matter and Weak Signals of Quantum Spacetime
PHYSICAL REVIEW D 95, 065009 (2017) Dark matter and weak signals of quantum spacetime † ‡ Sergio Doplicher,1,* Klaus Fredenhagen,2, Gerardo Morsella,3, and Nicola Pinamonti4,§ 1Dipartimento di Matematica, Università di Roma “La Sapienza”, Piazzale Aldo Moro 5, I-00185 Roma, Italy 2II Institut für Theoretische Physik, Universität Hamburg, D-22761 Hamburg, Germany 3Dipartimento di Matematica, Università di Roma “Tor Vergata”, Via della Ricerca Scientifica, I-00133 Roma, Italy 4Dipartimento di Matematica, Università di Genova, Via Dodecaneso 35, I-16146 Genova, Italy, and INFN Sezione di Genova, Genova, Italy (Received 29 December 2016; published 13 March 2017) In physically motivated models of quantum spacetime, a Uð1Þ gauge theory turns into a Uð∞Þ gauge theory; hence, free classical electrodynamics is no longer free and neutral fields may have electromagnetic interactions. We discuss the last point for scalar fields, as a way to possibly describe dark matter; we have in mind the gravitational collapse of binary systems or future applications to self-gravitating Bose-Einstein condensates as possible sources of evidence of quantum gravitational phenomena. The effects considered so far, however, seem too faint to be detectable at present. DOI: 10.1103/PhysRevD.95.065009 I. INTRODUCTION but their superpositions would, in general, not be—they would lose energy in favor of mysterious massive modes One of the main difficulties of present-day physics is the (see also [6]). lack of observation of quantum aspects of gravity. Quantum A naive computation showed, by that mechanism, that a gravity has to be searched without a guide from nature; the monochromatic wave train passing through a partially observed universe must be explained as carrying traces of reflecting mirror should lose, in favor of those ghost quantum gravitational phenomena in the only “laboratory” modes, a fraction of its energy—a very small fraction, suitable to those effects, i.e., the universe itself a few unfortunately, of the order of one part in 10−130 [5]. -
The Principle of Locality. Effectiveness, Fate and Challenges
The Principle of Locality. Effectiveness, fate and challenges Sergio Doplicher Dipartimento di Matematica University of Rome “La Sapienza” 00185 Roma, Italy October 26, 2018 Abstract The Special Theory of Relativity and Quantum Mechanics merge in the key principle of Quantum Field Theory, the Principle of Locality. We review some examples of its “unreasonable effectiveness” in giving rise to most of the conceptual and structural frame of Quantum Field Theory, especially in absence of massless particles. This effectiveness shows up best in the formulation of Quantum Field Theory in terms of operator algebras of local observables; this formulation is successful in digging out the roots of Global Gauge Invariance, through the analysis of Superselection Structure and Statistics, in the structure of the local observable quantities alone, at least for purely massive theories; but so far it seems unfit to cope with the Principle of Local Gauge Invariance. This problem emerges also if one attempts to figure out the fate of the Principle of Locality in theories describing the gravitational forces between elementary particles as well. An approach based on the need to keep an operational meaning, in terms of localisation of events, of the notion of Spacetime, shows that, in the small, the latter must loose arXiv:0911.5136v1 [math-ph] 26 Nov 2009 any meaning as a classical pseudoRiemannian manifold, locally based on Minkowski space, but should acquire a quantum structure at the Planck scale. We review the Geometry of a basic model of Quantum Spacetime and some attempts to formulate interaction of quantum fields on Quan- tum Spacetime. The Principle of Locality is necessarily lost at the Planck scale, and it is a crucial open problem to unravel a replacement in such theories which is equally mathematically sharp, namely a Prin- ciple where the General Theory of Relativity and Quantum Mechanics merge, which reduces to the Principle of Locality at larger scales. -
Reflections on the Renormalization Procedure for Gauge Theories
Available online at www.sciencedirect.com ScienceDirect Nuclear Physics B 912 (2016) 4–14 www.elsevier.com/locate/nuclphysb Reflections on the renormalization procedure for gauge theories Gerard ’t Hooft Institute for Theoretical Physics, EMMEΦ, Centre for Extreme Matter and Emergent Phenomena, Science Faculty, Utrecht University, P.O. Box 80.195, 3808TD, Utrecht, The Netherlands Received 4 April 2016; accepted 6 April 2016 Available online 12 April 2016 Editor: Hubert Saleur In memory of Raymond Stora 1930–2015 Abstract Various pieces of insight were needed to formulate the rules for working with gauge theories of the electro-magnetic, weak and strong forces. First, it was needed to understand how to formulate the Feynman rules. We had to learn that there are many different ways to derive them, and it was needed to know how different formulations of the gauge constraint lead to the same final results: the calculated values of the scattering amplitudes. The rules for dealing with the infinities that had to be subtracted were a big chal- lenge, culminating in the discovery of the Becchi–Rouet–Stora–Tyutin symmetry. Fond recollections of the numerous discussions the author had with Raymond Stora on this topic are memorised here. We end with some reflections on the mathematical status of quantum field theories, and the transcription of a letter by R. Stora to the author. © 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP3. 1. Introduction Around the year 1970, rapid changes took place in our views of elementary particle physics, and in particular the role of local gauge theories and spontaneous symmetry breaking in these theories. -
Adiabatic Limits and Renormalization in Quantum Spacetime
DOTTORATO DI RICERCA IN MATEMATICA XXXII CICLO DEL CORSO DI DOTTORATO Adiabatic limits and renormalization in quantum spacetime Aleksei Bykov A.A. 2019/2020 Docente Guida/Tutor: Prof. D. Guido Relatore: Prof. G. Morsella Coordinatore: Prof. A. Braides Contents 1 Introduction 4 2 Doplicher-Fredenhagen-Roberts Quantum Spacetime 11 2.1 Construction and basic facts . 11 2.2 Quantum fields on the DFR QST and the role of Qµν . 12 2.2.1 More general quantum fields in DFR QST . 13 2.3 Optimally localised states and the quantum diagonal map . 17 3 Perturbation theory for QFT and its non-local generalization 21 3.1 Hamiltonian perturbation theory . 22 3.1.1 Ordinary QFT . 22 3.1.2 Non-local case: fixing HI ............................. 26 3.1.3 Hamiltonian approach: fixing Hint ........................ 35 3.2 Lagrangian perturbation theories . 38 3.3 Yang-Feldman quantizaion . 41 3.4 LSZ reduction . 41 4 Feynman rules for non-local Hamiltonian Perturbation theory 45 5 Lagrangian reformulation of the Hamiltonian Feynman rules 52 6 Corrected propagator 57 7 Adiabatic limit 61 7.1 Weak adiabatic limit and the LSZ reduction . 61 7.1.1 Existence of the weak adiabatic limit . 61 7.1.2 Feynman rules from LSZ reduction . 64 7.2 Strong adiabatic limit . 65 8 Renormalization 68 8.1 Formal renormalization . 68 8.2 The physical renormalization . 71 8.2.1 Dispersion relation renormalisation . 72 8.2.2 Field strength renormalization . 72 8.3 Conluding remarks on renormalisation . 73 9 Conclusions 75 9.1 Summary of the main results . 75 9.2 Outline of further directions . -
A View on the European Strategy for Particle Physics
A VieW ON THE EurOPEAN StrATEGY FOR Particle Physics Contact Person: Michel SpirO ([email protected]) Worldwide, THE PARTICLE PHYSICS AND ACCELERATOR COMMUNITY IS AbstrACT VERY ACTIVELY WORKING TOWARDS THE NEXT MAJOR FACILITY. Based ON THE DESIGNS AND PERFORMANCE OF LINEAR AND CIRCULAR E+E* COLLIDERS IN THE 90 (Z) TO 365 (aboVE top-antitop) GeV CENTRe-of-mass ENERGY Range, WE CONSIDER A CIRCULAR COLLIDER AT CERN TO BE THE MOST ATTRACTIVE option. IT IS ALSO AN INVESTMENT IN THE FUTURE FOR A POSSIBLE LATER STAGE AS A 100 TeV HADRON collider. 1 OF5 A VieW ON THE EurOPEAN StrATEGY FOR Particle Physics The COMMUNITY OF PARTICLE PHYSICISTS IS PREPARING THE NEXT EurOPEAN Strat- EGY. IT WILL CONSIDER RECENT advances, SUCH AS THE IMPRESSIVE SUCCESS OF THE StandarD Model AND THE Higgs BOSON DISCOVERY, BUT ALSO ADDRESS funda- MENTAL QUESTIONS THAT REMAIN open. Exploring THE “UNIQUENESS” OF THE Higgs BOSON AND PLACING THE EMERGING UNDERSTANDING IN A LARGER CONTEXT (and NEW physics?) WILL BE ONE KEY ITEM ON OUR to-do list. While THE ONGOING AND PLANNED LHC EXPLOITATION WILL PROVIDE CONSIDERABLE PROGRess, IT IS GENERALLY AGREED THAT A NEW FACILITY, SOMETIMES DUBBED A “Higgs Factory”, WILL BE REQUIRED FOR THE AMBITIOUS PROGRAMME OF PRECISION MEASURements. CurrENTLY, THIS IS OBVIOUSLY THE DOMAIN OF AN E+E* collider. Linear OR Circular: THAT IS THE question. The OffERS THE POSSIBILITY TO Extend, IN principle, THE Linear Collider AVAILABLE COLLISION ENERGY AS PHYSICS indicates, AND ELECTRIC POWER AND fund- ING ALLOws. Longitudinal BEAM POLARIZATION CAN BE Exploited. IT HAS A disadvantage: ONLY ONE EXPERIMENT WILL TAKE DATA AT A GIVEN time.